Bag holding apparatus and method for packaging

ABSTRACT

A bag holder for packaging operations which removably supports a plurality of flexible bags preferably adjacent both a bag filling means and a fluid means for opening the bags prior to filling and for indicating the absence of bags on the holder. The bag holder comprises a support means including a frame, a removable wire wicket and a spring-biased back plate for urging the bags into filling position against the wicket. Associated with the springbiased plate is a fluid pressure sensitive signaling means which is actuable by a stream of air normally directed against the bags. When a supply of bags is on the wicket they prevent the signaling means from being actuated but when the supply of bags is exhausted the stream of air actuates the signaling means to indicate the supply of bags is exhausted. Another feature relates to means for pivoting the bag holder away from the bag filling means in order to facilitate the insertion of a fresh supply of bags on the holder.

United States Patent [1 1 Kihnke et al.

[451 Apr. 30, 1974 BAG HOLDING APPARATUS AND METHOD FOR PACKAGINGInventors: Lee S. Kihnke, Spring Lake; Dewey L. Thompson, Grand Haven,both of Mich.

Dake Corporation, Grand Haven, Mich.

Filed: May 17, 1972 App]. No.: 254,075

[73] Assignee:

[56] References Cited UN lTED STATES PATENTS 2/1950 Anglo 116/37 2/1973Fronczak 10/1969 Ness et a1. 116/65 X Primary ExaminerTravis S. McGeheeAttorney, Agent, or FirmHeneveld, Huizenga & Cooper A bag holder forpackaging operations which removably supports a plurality of flexiblebags preferably adjacent both a bag filling means and a fluid means foropening the bags prior to filling and for indicating the absence of bagson the holder. The bag holder comprises a support means including aframe, a removable wire wicket and a spring-biased back plate for urgingthe bags into filling position against the wicket. Associated with thespring-biased plate is a fluid pressure sensitive signaling means whichis actuable by a stream of air normally directed against the bags. Whena supply of bags is on the wicket they prevent the signaling means frombeing actuated but when the supply of bags is exhausted the stream ofair actuates the signaling means to indicate the supply of bags isexhausted.

Another feature relates to means for pivoting the bag holder away fromthe bag filling means in order to facilitate the insertion of a freshsupply of bags on the holder.

ABSTRACT 22 Claims, 5 Drawing Figures BAG HOLDING APPARATUS AND METHODFOR PACKAGING This invention relates to means or apparatus forsupporting a plurality of bags in a packaging machine and, moreparticularly, to a bag holding apparatus which removably supports aplurality of flexible bags preferably adjacent a bag filling means and afluid means for opening the bags prior to filling and for indicationwhen the bag holder is empty.

BACKGROUND OF THE INVENTION In the past, various apparatus forsupporting and holding bags during packaging operations have beendevised. Some of these prior bag holders have required the manualinsertion and removal of individual bags before and after the fillingoperation. Others of the prior bag holders have held a plurality of bagssuch that individual bags may be opened, filled and removed without theindividual insertion of additional bags. However, these latter supportmeans have included no means for indicating the absence of any bags onthe bag holder and thus, have not been able to prevent the operation ofthe packaging machine associated therewith when the bag holder is empty.Consequently, the utilization of the prior bag holders has requiredconstant attention to the packaging machines associated therewith byhuman operators in order to prevent the waste and spillage of materialsto be packaged when no bags are available and to maintain the constantoperation of the machine.

Thus, no efficient and reliable apparatus was available for holding,opening and indicating the absence of any of a supply of individualflexible bags and which would automatically prevent the operation of anassociated packaging apparatus when the bag holder was empty.

Further, the replenishing of bags on prior machines which held a supplyof bags at one time was difficult and time consuming. Thus, even withthe constant attention of the operator, valuable packaging time was lostmerely in inserting a fresh supply of bags.

SUMMARY OF THE INVENTION Accordingly, it is an object and feature of thepresent invention to provide a bag holding, opening and removingapparatus for packaging machines which includes automatic means forindicating the absence of any bags on the bag holder and automaticallyprevents the operation of the packaging machine when the bag holder isempty.

It is another object and feature of the present invention to provide abag holding, opening and removing apparatus for packaging machineshaving a fluid means for opening the individual bagsin preparation fortheir filling with the material to be packaged and a mechanical meansfor releasing the material to be packaged into the opened bag and forremoving the bag from the bag holder.

It is a further object and feature of the present invention to provide abag holder having a means for constantly urging the outermost bag in asupply of bags into the proper position for filling and removal fromsaid bag holder.

It is yet another object and feature of the present invention to providea bag holder having pivotal securing means for pivoting the bag holderinto a position facilitating the insertion and removal of hanger meansincluding a plurality of bags.

The object and attendant advantages of the present invention may beaccomplished by providing a bag holder for packaging machines comprisinga support means for holding a plurality of bags adjacent a filling meansfor filling the bags with material to be packaged. The support meanscomprises a bag frame pivotally mounted on a portion of the frame forthe packaging machine and includes a rear support plate and meansmounted perpendicularly thereto for removably holding a hanger meanswhich carries the plurality of bags. The bags hang from the hanger meansand rest on a spring-biased back plate which is slidably mountedperpendicularly to the rear support plate such that the back plateconstantly urges the plurality of bags against a cross member includedon said hanger means thereby forcing the plurality of bags away from therear support plate. The outermost bag on the plurality of bags is thusheld in the proper position adjacent the filling means in ready-to-fillposition. A retaining plate is removably mounted on the hangersupporting means in order to retain the hanger means and the pluralityof bags in their proper position. The support means also includes apivotal securing means which is slidably secured in a slotted membermounted on the packaging apparatus frame which may be selectivelysecured or released to allow the pivotal movement of the bag frame awayfrom the filling means thereby facilitating the removal of the retainingplate and the hanger means in order to refill the bag holding apparatus.

The bag holding apparatus further includes an aper ture in the biasedback plate which is connected with a fluid pressure-sensitive signalingmeans. When no bags are held by the bag holder, a fluid means, includinga nozzle directing a stream of compressed air at the aperture, directsthe stream of air into the aperture, thereby activating the fluidpressure-sensitive signaling means which indicates the absence of anybags and prevents the filling means from releasing any material to bepackaged. The fluid means also works in cooperation with the fillingmeans adjacent the bag holding apparatus in order to open the outermostbag held by the bag holding apparatus prior to the filling operation.

These and other objects, advantages and features of the invention willbecome apparent from a study of the following description taken inconjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary side elevationof the bag holding apparatus in combination with a packaging apparatus;

FIG. 2 is a front elevation of the bag holding appara tus in combinationwith the packaging apparatus taken along line 2-2 of FIG. 1;

FIG. 3 is an enlarged fragmentary side elevation of a portion of theapparatus shown in FIG. 1;

FIG. 4 is a fragmentary perspective view of a portion of the bag holdingapparatus; and

FIG. 5 is a fragmentary side elevation similar to FIG. 1 but showing thebag holding apparatus pivoted to a position for receiving a fresh supplyof bags.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings ingreater detail, FIG.

1 shows the bag holding apparatus in combination with a packagingapparatus including a filling means 60 and an infeed conveyor means 90.Generally speaking, support means or bag holding apparatus 10 issupported between frame members 11 and 12 which form a portion of theframe structure which also supports filling means 60. Bag holder isdisposed at an angle with the vertical generally beneath the lower endof the filling means such that the outermost bag 14 included in aplurality of bags 16 is properly positioned to be opened and removed bya fluid means 50 and filling means 60.

The filling means 60 which comprises a portion of the packagingapparatus used in conjunction with the bag holding apparatus 10, is ofthe type described in the concurrently filed application entitledPRODUCT PACKAGING APPARATUS invented by Lee S. Kihnke, Ser. No. 254,074,filed on even date herewith and incorporated by reference herein.Generally, the packaging apparatus includes a scale 62 havingcounterbalancing means or weights 63 which allows a predetermined weightto be set on scale 62 such that a certain predetermined amount ofmaterial to be packaged may be dispensed into bag 16 by filling means60. Scale 62'provides a supportifor filling means 60 suspended therefromby means of frame 64. The filling means 60 comprises a bucket 65 havingan upper opening 66 disposed adjacent the discharge end 92 of infeedconveyor means 90, and a lower end 67 disposed adjacent bags 16.Hingedly mounted on bucket 65 is a mechanical means or cover plate 70which pivots about rod 71.

Fluid power means including two air cylinders 72 and 74 mounted end toend provide power for opening cover plate or door 70 to a first openposition 75 and a second open position 76. First and second openpositions 75 and 76, shown by the phantom lines in FIG. 1, respectivelyallow the material'to be packaged held in bucket 65 to be released intothe awaiting outermost bag 14 (shown by the phantom lines in FIG. 1) andcause the filled bag to be removed from the bag holding apparatus 10respectively. Prior to the filling and removal of the bag 14, fluidmeans 50 opens bag 14 by means of a stream of compressed air aswill bedescribed more fully below.

Cooperating with filling means 60, is the infeed conveyor means 90,described in the concurrently filed application I entitled PACKAGINGAPPARATUS, invented by Lee S. Kihnke, Ser. No. 254,076, filed on evendate herewith and incorporated by reference herein. As partially shownin FIG. 1, conveyor means 90 includes a discharge end 92, flow divertinggates 94, and a recirculating conveyor means 96. The infeed conveyormeans 90 feeds a flow of material to be packaged to bucket 65 until apredetermined quantity of the material has been deposited in the bucket,when scale 62 signals that the predetermined weight has been reached.This signal causes flow diverting gates 94 to divert the flow ofmaterial from bucket 65 to recirculating conveyor 96 thereby preventingany waste and spillage of the material. Therefore, infeed conveyor means90 and filling means 60 work in cooperation with support means or bagholder 10 and fluid means 50 to provide a complete product or materialpackaging apparatus which can automatically open, fill, and remove asupply of bags 16 held by the bag holding apparatus 10 Referring now toFIGS. 1 through 5, the construction and operation of the novel supportmeans or bag holding apparatus 10 will now be described. Bag holdingapparatus 10 is mounted on frame member 11 by means of support members18 which include a support arm 19 (FIG. 3). Fastening means such asbolts 20 may be used for this purpose. Bag frame 22 is pivotally mountedon support arm 19 by means of pins 23 and pivot members 24. Bag frame 22includes a rear support plate 25 including wicket or hanger receivingelements 26 mounted perpendicularly thereon. A backing means or backplate 27 is slidably mounted on rods 28. The back plate 27 is biased bysprings 29 such that plate 27 is parallel to rear support plate 25 butis constantly urged against the plurality of bags 16 mounted on bagholding apparatus 10.

The plurality of bags 16 is fastened to bag frame 22 by means of ahanger means or wicket 30. Wicket 30 includes two parallel legs 31extending from and interconnected by a bight portion or cross member 32,which serves to restrain bag 16 when the wicket is in place in elements26. Each of the plurality of bags 16 includes two apertures 33 whichreceive legs 31 when the bags are placed thereon.

Bags 16 each include a flap 15 which is adjacent to and extends beyondthe opening 17 in each bag. Thus, when a plurality of bags 16 arestacked on wicket 30 by means of apertures 33 provided in flaps 15, andthe wicket 30 is mounted in apertures 34 provided in wicket receivingelements 26, the opening 17 of the outermost bag 14 will be in aposition immediately below the opening 67 of bucket 65. The outermostbag 14 is prevented from sliding off legs 31 by cross member 32, and theentire wicket and bag assembly when mounted in apertures 34 is preventedfrom moving by means of a removable restraining means or securing plate35 mounted on elements 26 by means of slots 36 and fastening means 37.As shown in FIG. 4, a right angle extension 38 on securing plate 35contacts cross member 32 of wicket 30 and securely holds the wicket inplace in apertures 34. Apertures 34 may be provided with grommets 39 orother liners in order to provide a frictional engagement of legs 31.Wicket 30 may thus be slidably inserted in apertures 34 and securelyheld by grommets 39.

As shown in FIGS. 1, 2 and 5, the'support means includes a securingmeans comprising a securing arm 40 pivotally mounted on pin 45, thelower portion of rear support plate 25 and cooperating with a slottedmember 41 such that the entire support means 10, including bag frame 22,may be selectively secured or released to pivot about pins 23 in an arcdownwardly and away from bucket 65. Securing arm 40 is threaded andreceives two nuts 46..Nuts 46 may be moved along the length of arm 40 toprovide an adjustable space along the arm for receiving slotted member41. Thus, the position of nuts 46 on arm 40 determines the angle atwhich the plurality of bags 16 supported on bag frame 22 is held beneathfilling means 60. When the last of the plurality of bags 16 has beenremoved from bag holding apparatus 10, securing arm 40 may be releasedfrom slotted member 41 thereby allowing bag frame 22 to pivot away fromfilling means and allowing the removal of securing plate 35 and emptywicket 30, as shown in FIG. 5. A fresh supply of bags carried on aseparate wicket 30 may then be inserted in apertures 34 and secured inplace by plate 35.'The bag frame may then be pivoted back to itsoperational position and secured in place by means of securing arm 40.

Cooperating with bag holding apparatus 10, is fluid means 50 asdescribed in the co-pending application, Ser. No. 254,074, referred toabove. Fluid means 50 comprises a conduit or tube 51 having a fluid flowdirecting means or nozzle 52 at the end thereof. Conduit 51 is connectedto a main air supply, a portion of which is shown in FIG. 1 at 53.Nozzle 52 is positioned so as to direct a stream of compressed air fromair supply 53 past the lowermost extremity of mechanical means or coverplate 70. A portion of the stream of compressed air will be deflected bycover plate 70 towards opening 17 of the outermost bag 14 therebyopening and filling the bag with air. Upon a signal given by scale 62,as described above, the cover plate 70 will then be pivoted into itsfirst open position 75, as described above, and cover plate 70 willswing into the already open bag 14 thereby allowing material to bepackaged to slide from bucket 65 into bag 14. The cover plate 70 maythen be moved to its second open position 76, as also described above,which movement forceably removes bag 14 from flag 15 along theperforated line shown in FIG. 4 and allows the filled bag to drop into awaiting receptacle positioned below the bag holding apparatus. Thisoperation will be repeated by the filling means 60 a number of timesuntil all of the plurality of bags 16 have been used. The removal of thelast bag from bag holding apparatus 10 allows the operation of anadditional feature as described below.

The additional operation comprises a method for detecting the absence ofbags on the bag holding apparatus and for stopping the dispensing ofmaterial when the absence of any bags is detected. When the last bag 14has been urged into position by biased backing plate 27, filled andremoved by filling means 60 and cover plate 70, an additional portion ofthe fluid means 50 or an indicating means mounted on bag holdingapparatus 10 is activated. Back plate 27 includes an aperture or port 42which is connected to a fluid pressure sensitive signaling or switchmeans 43 mounted on rear support plate 25 by a communicating or flexibletube 44. Port 24 is positioned in back plate 27 directly in line withthe stream of air flowing from nozzle 52 past the lowermost extremity ofcover plate 70 such that, when the last bag 14 has been removed fromapparatus 10, the flow of compressed air will directly enter port 42. Abag in position as supported by apparatus 10 normally blocks the flow ofair with its. exposed side. However, when the bag is absent, air willenter port 42 which is positioned on the opposite side of the normal bagposition. The entering of the flow of compressed air into port 42 causesan increase in fluid pressure in communicatin g or flexible tube 44which in turn expands a bellows (not shown) in fluid pressure sensitivesignaling or switch means 43 thereby closing a switch (not shown). Theclosing of the switch in fluid pressure sensitive signaling means 43activates a bag-empty or no-bag electrical signaling circuit (not shown)which in turn activates and diverts gates 94 across the flow of materialon infeed conveyor 90 thereby preventing material from entering bucket65 and being released bycover plate 70. An indicating light is alsoturned on by signaling means 43 to visually alert the packagingapparatus operator that the bag holder is empty. Consequently, it willbe understood that the indicating means comprising port 42, signalingmeans 43 and tube 44, in combination with the remainder of fluid means50, comprise a means for indicating the absence of any bags on bagholding apparatus 10. This indicating means prevents the operation ofthe packaging apparatus until a fresh supply of bags is inserted on bagholder 10 and the bagempty signaling circuit is manually shut off.

- Therefore, it will be apparent that the bag holding apparatus orsupport means 10, in combination with the fluid means 50, provides anovel and useful means for supporting a plurality of bags in a packagingmachine or apparatus. The bag holder and fluid means both insure thecontinuous and efficient operation of the packaging apparatus as a wholeand yet, control the operation of the packaging apparatus when the bagholders supply of bags is exhausted. Thus, the efficient and automaticoperation of the packaging apparatus is insured since the bag holdingapparatus and fluid means will prevent the waste and spillage of thematerial to be packaged when no bags are left on the bag holdingapparatus. It will also be observed that the bag holding apparatus 10may be utilized to secure many types of flexible bags although in itspreferred embodiment, its use is designed for lightweight, flexibleplastic bags such as those used in the food processing industry.

While one form of the invention has been shown and described, otherforms will now be apparent to those skilled in the art. Therefore, itwill be understood that the embodiment shown in the drawings anddescribed above, is merely for illustrative purposes, and is notintended to limit the scope of the invention which is defined by theclaims which follow.

The embodiments .of the invention in which an exclusive property orprivilege is claimed are defined as follows:

l. A bag holding apparatus for packaging machines comprising incombination: support means for holding removable bags adjacent a bagfilling means; and fluidoperated switch means for indicating the absenceof said bag on said support means; said switch means including means fordirecting a stream of fluid against one surface of a bag when held bysaid support means and means responsive to said fluid flow forpreventing operation of a packaging machine when said bag is absent,said responsive means being located in registry with said fluid flow andadjacent a surface of said bag opposite said one surface when said bagis held on said support means.

2. A bag holding apparatus for packaging machines comprising incombination: support means for holding removable bags adjacent a bagfilling means; and fluid operated switch means for indicating theabsence of said bag on said support means; said support means comprisinga frame for supporting said bags in a position immediately adjacent saidbag filling means, hanger means for removably mounting said bags on saidframe, and backing means for constantly urging said bags into saidposition immediately adjacent said filling means.

3. A bag holding apparatus as described in claim 2 wherein said fluidoperated switch means comprises fluid flow directing means and fluidpressure sensitive shut-off means, said fluid flow directing means beingpositioned to direct a fluid flow against bags supported against saidbacking means and into said fluid pressure sensitive shut-off means foractuating the same.

4. A bag holding apparatus as described in claim 3 wherein said hangermeans comprises a U-shaped wire wicket, said U-shaped wire wicket havingtwo, parallel leg portions each having one of their ends extending in adirection toward the plane of said backing means and their other endsinterconnected by a bight portion; said bight portion preventing bagsbeing on said legs from sliding off said wicket legs when said wicket ismounted on said frame; said backing means including a springbiased backplate for constantly urging bags being on said legs against said bightportion so as to position the tops of the bags in position to be openedby said fluid flow directing means.

5. A bag holding apparatus as described in claim 4 wherein said fluidflow directing means comprises a nozzle directing a flow of compressedair.

6. A bag holding apparatus as described in claim 3 wherein said fluidpressure sensitive shut-off means comprises an aperture formed in saidbacking means in line with said flow of compressed air, an expandablefluid servo unit including an electrical switch and a flexible tubeconnecting said aperture with said servo unit such that, in the absenceof bags on said wicket,

- said flow of compressed air will enter said aperture, be

communicated by said tube to said servo unit, and actuate said servounit, thereby closing said electrical switch.

7. A bag holding apparatus as described in claim 4 wherein there isprovided wicket support means for removably supporting said wicket onsaid support means and pivot means for selectively pivoting said supportmeans and said wicket support means out of their normal position inwhich they support bags in a ready-tofill position whereby said wicketmay be removed from said wicket support means and another of saidwickets, including at least one bag, may be mounted on said frame.

8. The bag holding apparatus of claim 7 in which the support means ispivoted at its upper end and a locking means is provided at its lowerend for locking the support into ready-to-fill position; said lockingmeans being releaseable for permitting'pivoting of said support meansabout said pivot means.

9. Apparatus for opening bags and indicating the absence of bags on abag holder for packaging machines comprising fluid flow directing meansfor directing a stream of fluid toward a bag holder and for opening andpositioning the mouth of a bag on said holder for receiving material tobe packaged from a packaging machine; and fluid pressure sensitivesignaling means including means responsive to the pressure of saidstream of fluid for providing a signal indicating when said bags areabsent; said flow being directed by said directing means such that whensaidbags are supported on said holder, said stream will open andposition said bag mouth, and when no bags are supported on said bagholder, said stream will activate said fluid pressure sensitivesignaling means and indicate the absence of said bags.

10. Apparatus as described in claim 9 wherein said fluid flow directingmeans comprises a nozzle arranged to direct a stream of compressed airagainst the outermost bag supported by said holder such that saidoutermost bag is opened and filled with said air.

11. Apparatus for opening bags and indicating the absence of bags on abag holder for packaging machines comprising fluid flow directing means,and fluid pressure sensitive signaling means, said fluid flow directingmeans adapted to direct a stream of fluid towardsaid bag holder suchthat when said bags are supported on said holder, said stream will opensaid bags, and when no bags are supported on said bag holder, saidstream will activate said fluid pressure sensitive signaling means andindicate the absence of said bags; said fluid flow directing meanscomprising a nozzle arranged to direct a stream of compressed airagainst the outermost bag supported by said holder such that saidoutermost bag is opened and filled with said air; said fluid pressuresensitive signaling means comprising an aperture formed in said bagholder behind the area in which said bags are normally supported, anexpandable fluid servo unit, and a flexible tube connecting saidaperture with said servo unit, said aperture being in line with saidstream of compressed air such that, in the absence of any bags on saidholder, said stream of air enters said aperture, is transmitted to saidservo unit by said tube, and actuates said servo unit thereby signalingthe absence of said bags.

12. A bag holding apparatus for packaging'machines comprising a movablesupport means for holding a supply of removable bags adjacent a bagfilling means; and securing means for selectively restraining andallowing movement of said support means whereby the insertion of a freshsupply of removable bags is facilitated; said support means beingpivotally mounted adjacent a bag filling means; said securing meanscomprising a pivot arm and a fixed member separate from said supportmeans, said pivot arm adapted to be selectively engaged and disengagedwith said fixed member whereby said support means is allowed to pivotaway from said bag filling means. in order to insert a fresh supply ofbags.

13. A bag holding apparatus as described in claim 12 wherein saidsupport means comprises a frame for supporting said bags in a positionimmediately adjacent said bag. filling means, hanger means for removablymounting said bags on said frame, and backing means for constantlyurging said bags into said position immediately adjacent said fillingmeans.

14. A bag holding apparatus as described in claim 13 wherein said pivotarm is pivotally mounted on said frame and said fixed'member is rigidlymounted on said bag filling means.

15. A bag holding apparatus as described in claim 14 wherein said pivotarm is adjustable such that said support means may be held in variouspositions relative to said bag filling means. I

16. A bag holding apparatus as described in claim 13 wherein said hangermeans comprises a wicket removably insertable in apertures provided insaid frame, said wicket adapted to support a supply of bags adjacentsaid bag filling means when in place on said frame, said support meansbeing restrained adjacent said bag filling means by said securing means;said support means further including a retaining plate removably mountedon said frame for retaining said wicket on said frame; said securingmeans arranged to allow said support means to be pivoted away from saidbag filling means whereby removal of said retaining plate and wicket isfacilitated.

17. A bag holding apparatus as described in claim 16 wherein said wicketcomprises a U-shaped wire wicket, said U-shaped wire wicket having two,parallel leg portions each having one of their ends extending in adirection toward the plane of said backing means and their other endsinterconnected by a bight portion; said bight portion preventing bagsbeing on said legs from sliding off said wicket legs when said wicket ismounted on said frame; said backing means including a springbiased backplate for constantly urging bags being on said legs against said bightportion so as to position the tops of the bags in position to be openedby said fluid flow directing means.

18. A bag holding apparatus as described in claim 17 wherein saidsupport means is pivoted at its upper end and said securing means isprovided at its lower end for restraining said support means in aready-to-fill position.

19. In a method of packaging material comprising:

providing a bag for receiving material;

opening said bag with a stream of fluid;

depositing said material in said bag;

the improvement comprising detecting a stream of fluid in order toindicate the absence of a bag; said stream being directed against oneside of said bag position when said bag is present; said stream beingdetected on the opposite side of said bag position when said bag isabsent.

20. A method in accordance with claim 19 wherein said opening of saidbag and said detecting of said stream of fluid are accomplished with thesame stream of fluid.

21. A method in accordance with claim 19 wherein said detection of saidstream of fluid initiates the stopping of said deposition of saidmaterial.

22. A bag holding apparatus for packaging machines comprising apivotally movable support means for holding a supply of removable bagsadjacent a bag filling means; and securing means for selectivelyrestraining and allowing pivotal movement of said support means wherebythe insertion of a fresh supply of removable bags is facilitated; saidsupport means including a frame for supporting said bags in a positionimmediately adjacent said bag filling means, hanger means for removablymounting said bags on said frame, and backing means for constantlyurging said bags into said position immediately adjacent said fillingmeans.

1. A bag holding apparatus for packaging machines comprising incombination: support means for holding removable bags adjacent a bagfilling means; and fluid-operated switch means for indicating theabsence of said bag on said support means; said switch means includingmeans for directing a stream of fluid against one surface of a bag whenheld by said support means and means responsive to said fluid flow forpreventing operation of a packaging machine when said bag is absent,said responsive means being located in registry with said fluid flow andadjacent a surface of said bag opposite said one surface when said bagis held on said support means.
 2. A bag holding apparatus for packagingmachines comprising in combination: support means for holding removablebags adjacent a bag filling means; and fluid operated switch means forindicating the absence of said bag on said support means; said supportmeans comprising a frame for supporting said bags in a positionimmediately adjacent said bag filling means, hanger means for removablymounting said bags on said frame, and backing means for constantlyurging said bags into said position immediately adjacent said fillingmeans.
 3. A bag holding apparatus as described in claim 2 wherein saidfluid operated switch means comprises fluid flow directing means andfluid pressure sensitive shut-off means, said fluid flow directing meansbeing positioned to direct a fluid flow against bags supported by saidframe such that said fluid flow opens and fills said bags therebyproperly positioning said bag means to receive material; and, in theabsence of any bag means on said support means, directing said fluidflow against said backing means and into said fluid pressure sensitiveshut-off means for actuating the same.
 4. A bag holding apparatus asdescribed in claim 3 wherein said hanger means comprises a U-shaped wirewicket, said U-shaped wire wicket having two, parallel leg portions eachhaving one of their ends extending in a direction toward the plane ofsaid backing means and their other ends interconnected by a bightportion; said bight portion preventing bags being on said legs fromsliding off said wicket legs when said wicket is mounted on said frame;said backing means including a spring-biased back plate for constantlyurging bags being on said legs against said bight portion so as toposition the tops of the bags in position to be opened by said fluidflow directing means.
 5. A bag holding apparatus as described in claim 4wherein said fluid flow directing means comprises a nozzle directing aflow of compressed air.
 6. A bag holding apparatus as described in claim3 wherein said fluid pressure sensitive shut-off means comprises anaperture formed in said backing means in line with said flow ofcompressed air, an expandable fluid servo unit including an electricalswitch and a flexible tube connecting said aperture with said servo unitsuch that, in the absence of bags on said wicket, said flow ofcompressed air will enter said aperture, be communicated by said tube tosaid servo unit, and actuate said servo unit, thereby closing saidelectrical switch.
 7. A bag holding apparatus as described in claim 4wherein there is provided wicket support means for removably supportingsaid wicket on said support means and pivot means for selectivelypivoting said support means and said wicket support means out of theirnormal position in which they support bags in a ready-to-fill positionwhereby said wicket may be removed from said wicket support means andanother of said wickets, including at least one bag, may be mounted onsaid frame.
 8. The bag holding apparatus of claim 7 in which the supportmeans is pivoted at its upper end and a locking means is provided at itslower end for locking the support into ready-to-fill position; saidlocking means being releaseable for permitting pivoting of said supporTmeans about said pivot means.
 9. Apparatus for opening bags andindicating the absence of bags on a bag holder for packaging machinescomprising fluid flow directing means for directing a stream of fluidtoward a bag holder and for opening and positioning the mouth of a bagon said holder for receiving material to be packaged from a packagingmachine; and fluid pressure sensitive signaling means including meansresponsive to the pressure of said stream of fluid for providing asignal indicating when said bags are absent; said flow being directed bysaid directing means such that when said bags are supported on saidholder, said stream will open and position said bag mouth, and when nobags are supported on said bag holder, said stream will activate saidfluid pressure sensitive signaling means and indicate the absence ofsaid bags.
 10. Apparatus as described in claim 9 wherein said fluid flowdirecting means comprises a nozzle arranged to direct a stream ofcompressed air against the outermost bag supported by said holder suchthat said outermost bag is opened and filled with said air. 11.Apparatus for opening bags and indicating the absence of bags on a bagholder for packaging machines comprising fluid flow directing means, andfluid pressure sensitive signaling means, said fluid flow directingmeans adapted to direct a stream of fluid toward said bag holder suchthat when said bags are supported on said holder, said stream will opensaid bags, and when no bags are supported on said bag holder, saidstream will activate said fluid pressure sensitive signaling means andindicate the absence of said bags; said fluid flow directing meanscomprising a nozzle arranged to direct a stream of compressed airagainst the outermost bag supported by said holder such that saidoutermost bag is opened and filled with said air; said fluid pressuresensitive signaling means comprising an aperture formed in said bagholder behind the area in which said bags are normally supported, anexpandable fluid servo unit, and a flexible tube connecting saidaperture with said servo unit, said aperture being in line with saidstream of compressed air such that, in the absence of any bags on saidholder, said stream of air enters said aperture, is transmitted to saidservo unit by said tube, and actuates said servo unit thereby signalingthe absence of said bags.
 12. A bag holding apparatus for packagingmachines comprising a movable support means for holding a supply ofremovable bags adjacent a bag filling means; and securing means forselectively restraining and allowing movement of said support meanswhereby the insertion of a fresh supply of removable bags isfacilitated; said support means being pivotally mounted adjacent a bagfilling means; said securing means comprising a pivot arm and a fixedmember separate from said support means, said pivot arm adapted to beselectively engaged and disengaged with said fixed member whereby saidsupport means is allowed to pivot away from said bag filling means inorder to insert a fresh supply of bags.
 13. A bag holding apparatus asdescribed in claim 12 wherein said support means comprises a frame forsupporting said bags in a position immediately adjacent said bag fillingmeans, hanger means for removably mounting said bags on said frame, andbacking means for constantly urging said bags into said positionimmediately adjacent said filling means.
 14. A bag holding apparatus asdescribed in claim 13 wherein said pivot arm is pivotally mounted onsaid frame and said fixed member is rigidly mounted on said bag fillingmeans.
 15. A bag holding apparatus as described in claim 14 wherein saidpivot arm is adjustable such that said support means may be held invarious positions relative to said bag filling means.
 16. A bag holdingapparatus as described in claim 13 wherein said hanger means comprises awicket removably insertable in apertures provided in said frame, saidwicket adapted to support a supply of bags adjacent said bag fillingmeans when in place on said frame, said support means being restrainedadjacent said bag filling means by said securing means; said supportmeans further including a retaining plate removably mounted on saidframe for retaining said wicket on said frame; said securing meansarranged to allow said support means to be pivoted away from said bagfilling means whereby removal of said retaining plate and wicket isfacilitated.
 17. A bag holding apparatus as described in claim 16wherein said wicket comprises a U-shaped wire wicket, said U-shaped wirewicket having two, parallel leg portions each having one of their endsextending in a direction toward the plane of said backing means andtheir other ends interconnected by a bight portion; said bight portionpreventing bags being on said legs from sliding off said wicket legswhen said wicket is mounted on said frame; said backing means includinga spring-biased back plate for constantly urging bags being on said legsagainst said bight portion so as to position the tops of the bags inposition to be opened by said fluid flow directing means.
 18. A bagholding apparatus as described in claim 17 wherein said support means ispivoted at its upper end and said securing means is provided at itslower end for restraining said support means in a ready-to-fillposition.
 19. In a method of packaging material comprising: providing abag for receiving material; opening said bag with a stream of fluid;depositing said material in said bag; the improvement comprisingdetecting a stream of fluid in order to indicate the absence of a bag;said stream being directed against one side of said bag position whensaid bag is present; said stream being detected on the opposite side ofsaid bag position when said bag is absent.
 20. A method in accordancewith claim 19 wherein said opening of said bag and said detecting ofsaid stream of fluid are accomplished with the same stream of fluid. 21.A method in accordance with claim 19 wherein said detection of saidstream of fluid initiates the stopping of said deposition of saidmaterial.
 22. A bag holding apparatus for packaging machines comprisinga pivotally movable support means for holding a supply of removable bagsadjacent a bag filling means; and securing means for selectivelyrestraining and allowing pivotal movement of said support means wherebythe insertion of a fresh supply of removable bags is facilitated; saidsupport means including a frame for supporting said bags in a positionimmediately adjacent said bag filling means, hanger means for removablymounting said bags on said frame, and backing means for constantlyurging said bags into said position immediately adjacent said fillingmeans.